2021’s Partial Lunar Eclipse:
A lunar eclipse occurs when Earth’s shadow block the sun’s light, that reflects off the moon. Lunar eclipses are categorized into three types:
1) partial – When the Earth moves between the Full Moon and the Sun, but they are not perfectly aligned. Instead, only part of the Moon’s surface moves into the Earth’s shadow.
2) penumbral – When the Earth, Sun, and Moon are imperfectly aligned in such a way that the Earth’s outer shadow falls on the Moon’s surface.
3) total – When the Earth, Moon, and Sun are in complete alignment to where Earth’s shadow completely falls on the Full Moon. This causes the Moon’s surface to completely darken or redden.
This year’s partial lunar eclipse was considered the longest one in a millennium (one thousand years)! It took about 3 hours, 28 minutes, and 23 seconds for the partial ellipse to occur. The last long partial eclipse happened on February 18th, 1440 – which clocked to about 3 hours, 28 minutes, and 46 seconds. This partial lunar eclipse will remain the longest one for 648 years until February 8th, 2669 – which is predicted to clock to about 3 hours, 30 minutes, and 2 seconds!
So why what the eclipse of 2021 so long? Well, the eclipse was long for two main causes: (1) the Moon’s orbital speed and (2) the near-totality of the eclipse (even though it is still considered a partial eclipse). The Moon’s orbit around the Earth is not a perfect circle. In actuality, the Earth is not in the center within the orbit, so sometimes the Moon is closer to the Earth, and other times it is farther. This variation in distance effects the Moon’s orbital speed (father = slower; closer = faster). Thus, the Moon is at a farther point in its orbit around the Earth, and as a result, it moves slowly through Earth’s shadow (which is indicated by the darkening or reddening of the Moon’s surface). Since the eclipse is almost-total, the Moon takes a longer time in the Earth’s shadow than a typical “partial” eclipse.
Are you curious of when the next lunar eclipse will happen? Well, the next total lunar eclipse (A.K.A.: “blood moon”) will happen May 15-16, 2022. It will be visible from North and South America, Africa, Europe, and parts of Asia. Stay tuned to space news to stay updated!
Below are pictures that I took with my iPhone of the raw partial lunar eclipse that occurred on Friday, November 19th. I stayed up until 4am to watch it happen! I was able to take these pictures while standing on Howey’s Physics Observatory! One of my friends even got to take a picture through the telescope of the moon during the eclipse. Here are the pictures below.